This invention is directed to a method for preparing imides from compounds having a sulfonyl fluoride functional group. The imides so prepared are useful in a variety of catalytic and electrochemical applications.
Compounds having a sulfonyl fluoride functional group are well known in the art. In particular, vinyl ethers and olefins having a fluorosulfonyl fluoride group have been found to be particularly useful as monomers for copolymerization with tetrafluoroethylene, ethylene, vinylidene fluoride and other olefinic and fluoroolefinic monomers to form polymers which, upon hydrolysis are converted to highly useful ionomers. One area of important use for ionomers so formed is in the area of lithium batteries. See for example Connolly et all U.S. Pat. No. 3,282,875 and commonly assigned Ser. No. 09/023,244 U.S. Pat. No. 6,025,092 and Ser. No. 09/061,132 U.S. Pat. No. 6,100,324.
It is also known to prepare imides from compounds having sulfonyl fluoride functionality particularly fluorinated organic sulfonyl imides are known in the art. For example, DesMarteau, U.S. Pat. No. 5,463,005, discloses substituted perfluoro-olefins of the formula 
where Xxe2x95x90CH or N, Zxe2x95x90H, K, Na, or Group I or II metal, R=one or more fluorocarbon groups including fluorocarbon ethers and/or sulfonyl groups and/or perfluoro non-oxy acid groups, Y=perfluoroal or F, and m=0 or 1.
Xue, Ph.D. thesis, Clemson University, 1996, discloses the formation of the monomer
CF2xe2x95x90CFxe2x80x94OCF2CF2SO2N(Na)SO2CF3
by reaction of CF2xe2x95x90CFxe2x80x94OCF2CF2SO2Cl with CF3SO2NHNa in the presence of Na2CO3 in acetonitrile. However, Xue""s method is not applicable to the sulfonyl fluoride species without first protecting the double bond.
Further disclosed by Xue, op.cit, is CF3SO2NNa2 made by combining CF3SO2NHNa and NaH in THF and reacting for four hours at room temperature. The inventors hereof have determined that Xue""s method of preparation provides a conversion of less than 10% from CF3SO2NHNa to CF3SO2NNa2. No method of separation is provided, nor is any method provided for preparing the CF3SO2NNa2 at higher yield. Thus no means is provided for producing CF3SO2NNa2 in a highly purified state. Xue suggests that CF3SO2NNa2 can be reacted with a cyclic sulfone of the formula: 
to produce the vinyl ether monomer, CF2xe2x95x90CFxe2x80x94OCF2CF2SO2N(Na)SO2CF3. Also disclosed by Xue is a reaction between CF2xe2x95x90CFOCF2CF2SO2F and CF3SO2NHNa to produce an unusable complex mixture of products. Xue makes no suggestion that CF3SO2NNa2 is effective at converting sulfonyl fluoride containing compounds to imides.
MeuBdoerffer et al., Chemiker Zeitung, 96. Jahrgang (1972) No. 10, 582-583 discloses a method for synthesizing RSO2NH2 wherein R is perfluoroalkyl.
Feiring et al., WO 9945048(A1), provides a method for imidizing fluorinated vinyl ether monomers containing a sulfonyl fluoride group by first protecting the double bond and then converting the sulfonyl fluoride into an imide.
Armand et al, EPO 0 850 920 A2, discloses a method for imidizing sulfonyl fluoride and chloride species containing aromatic rings.
The present invention provides for a process comprising: Contacting, in a liquid dispersion or solution, a composition comprising a sulfonyl amide salt represented by the formula:
(R2SO2NMb)3-bMxe2x80x2cxe2x80x83xe2x80x83(III)
wherein R2 is aryl, fluoro-aryl, or XCF2xe2x80x94 where X is H, halogen, fluorinated or non-fluorinated linear or cyclic alkyl radicals having 1-10 carbons, optionally substituted by one or more ether oxygens, Mxe2x80x2 is an alkaline earth metal, b=1 or 2, c=0 or 1, M is an alkaline earth when b is 1 or an alkali metal when b is 2 and c=0, and M is alkali metal when b=1 and c=1, with the proviso that c is not equal to 1 when b=2 with
a non-polymeric sulfonyl fluoride composition represented by the formula R1(SO2F)m (IV)
wherein m=1 or 2, where, when m=1, R1 is a fluorinated or non-fluorinated, saturated or unsaturated hydrocarbyl radical, except perfluoroolefin, having 1-12 carbons optionally substituted by one or more ether oxygens, or tertiary amino; or, when m=2, R1 is a fluorinated or non-fluorinated, saturated or unsaturated hydrocarbylene, except perfluoroalylene, radical having 1-12 carbons optionally substituted by one or more ether oxygens;
or with a polymeric sulfonyl fluoride composition comprising monomer units represented by the formula
xe2x80x94[CZ2CZ(R3SO2F)]xe2x80x94xe2x80x83xe2x80x83(V)
wherein R3 is a diradical selected from the group consisting of fluorinated or non-fluorinated allylene, including oxyalkylene or fluorooxyalkylene, but not perfluoroalkylene, and each Z is independently hydrogen or halogen, and the Zs need not be the same; and,
causing them to react to form a non-polymeric imide composition represented by the formula: 
wherein y=1 or 2, M is an alkali when y is 1 or an alkaline earth metal when y is 2, m=1 or 2, where, when m=1, R1 is a fluorinated or non-fluorinated, saturated or unsaturated hydrocarbyl radical, except perfluoroolefin, having 1-12 carbons optionally substituted by one or more ether oxygens, or tertiary amino; or, where m=2, R1 is a fluorinated or non-fluorinated, saturated or unsaturated hydrocarbylene, except perfluoroalkylene, radical having 1-12 carbons optionally substituted by one or more ether oxygens, with the proviso that when y=2 and m=2, M may represent a combination of alkali and alkaline earth metals;
or, in the alternative, a polymeric imide composition comprising monomer units represented by the formula: 
wherein y=1 or 2; R3 is a diradical selected from the group consisting of fluorinated or non-fluorinated alkylene, including oxyalkylene or fluorooxyalkylene, each Z is independently hydrogen or halogen, wherein the Z""s need not be the same; R2 is aryl, fluoro-aryl, or XCF2xe2x80x94where X is H, halogen, fluorinated or non-fluorinated linear or cyclic alkyl radicals having 1-10 carbons, optionally substituted by one or more ether oxygens; M is an alkali when y is 1 or an alkaline earth metal when y is 2.
As used herein, the term xe2x80x9creactingxe2x80x9d is intended to mean allowing or to allow at least two components in a reaction mixture to react to form at least one product. xe2x80x9cReactingxe2x80x9d may optionally include stirring and/or heating or cooling.